Cytomegalovirus (CMV) can be devastating in the patient who has undergone an allogenic bone marrow transplant. Rapid detection of CMV infection in these patients can be lifesaving, allowing the prompt administration of anti-CMV drugs. There is also a clinical need for a quantitative measure of the CMV present in the clinical specimen to allow for monitoring therapy and predicting emergence of drug-resistant variants. A research assay has been developed by a commercial vendor that allows the use of quantitative polymerase chain reaction (PCR) to measure the CMV DNA extracted from whole blood. We are evaluating this PCR assay using peripheral blood leukocytes collected by American Medical Laboratories and comparing the results with those of the CMV antigenemia quantitative assay (performed at American Medical Laboratories) that detects the presence of CMV pp65 early structural protein in polymorphonuclear leukocytes and monocytes. Specimens with discrepant results will be sent to Microbiology Reference Laboratories to be evaluated using a second PCR assay. Results thus far indicate that the commercial PCR is at least as sensitive as the CMV antigenemia assay. More specimens need to be tested for a statistically valid comparison to be made.This project has been discontinued.